• The Korean Journal of Mycology
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• v.12 no.4
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• pp.159-163
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• 1984

Sphaerotheca fuliginea (Schlecht. ex Fr.) Poll. has been recorded on 13 plant species in Korea, to which the authors add 10 additional host plants. The taxonomic concept of S. fuliginea proposed by Blumer in 1933 was adopted here.

• Mycobiology
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• v.28 no.1
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• pp.51-53
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• 2000

The powdery mildew of safflower (Carthamus tinctorius L.) extensively occurred at 1999 at the experimental farm of Kyongsangnam-do Agricultural Research and Extension Services. Both sides of the leaves and the older stems were covered with the fungus, and then the leaves and stems turned yellow. The conidia, conidiophores and perithecia were observed on the leaf lesion. Perithecia were ellipsoidal, $80-117\;{\mu}m$ in diameter. Asci were subglobose and $84{\sim}99{\times}59{\sim}73\;{\mu}m$ in size. Ascospore were ellipsoidal to ovoid, and $15{\sim}34{\times}11{\sim}23\;{\mu}m$ in size. Conidia were ellipsoid to barrel-shaped, $25{\sim}37{\times}11{\sim}22\;{\mu}m$ in size and formed in long chains. The causal organism was identified as Sphaerotheca fuliginea. This is the first report on powdery mildew of safflower caused by Sphaerotheca fuliginea in Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4854-4862
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• 2010

Twenty five compounds isopropylmethylphenyl benzenesulfonate derivatives of thymol (1), 4-isopropyl-3-methylphenol (2), 5-isopropyl-3-methylphenol (3), 4-isopropylphenol (4), and 2-isopropylphenol (5) derivatives were synthesized. These compounds were analyzed for their structural confirmation with IR, GC/MS, and $^1H$-NMR. Synthetic compounds were tested against phytopathogenic fungi activities such as Pyrcularia grisea, Rhizoctonia solani, Phytophthora infestans, Colletotrichum orbiculare, and Sphaerotheca fusca. 2-Isopropyl-5-methylphenyl o-toluenesulfonate (1a), 2-isopropylphenyl 2,4,5-trichloro-benzenesulfonate (5b) and 2-isopropylphenyl 2-methyl-5-nitrobenzenesulfonate (5e) showed a potent in vivo antifungal activity against Pyrcularia grisea, Phytophthora infestans and Sphaerotheca fusca.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.234-236
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• 1999

Sphaerotheca fuliginea has previously been recorded as a powdery mildew fungus on dahlia (Dahlia pinnata) in Korea. Six collections of the dahlia mildew by the authors since 1993, however, show that the fungus does not contain conspicuous fibrosin bodies and has sinuate edge lines on conidiophores. These characters clearly indicate that the fungus causing the powdery mildew on dahlia in Korea is Erysiphe cichoracearum. On the other hand, one plant of dahlia grown in a pot was found to be infected with S. fusca (= S. fuliginea s. lat.). It is supposed to be unusual. Therefore, two species of dahlia mildew fungi are distributed and E. cichoracearum is the main cause of dahlia mildew in Korea.

• The Plant Pathology Journal
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• v.27 no.1
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• pp.8-13
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• 2011

The induced resistance of cucumber leaves treated with oligochitosan to the infection of the cucumber powdery mildew, Sphaerotheca fuliginea, was investigated using transmission electron microscopy. The results showed that when the plants were treated with oligochitosan and challenged with inoculum, a significant decrease of the disease occurred. The mycelial development in the treated leaves was markedly inhibited. The cytoplasm of the powdery mildew mycelium was aggregated, with its organelles disintegrated and the cytoplasm collapsed. The protoplasm in haustoria became electron-dense. Haustoria became malformed, their organelles disintegrated, the hausterial wall thickened and eventually the whole complex necrotized. The host cells produced defence structures and materials associated with infection and a hypersensitive response. The host cell wall was thickened and deeply stained; several layers of papilla structure were produced under the cell wall; dark materials were deposited between the cell wall and plasmalemma; extrahaustorial plasmalemma was deeply stained and extrahaustorial matrix appositions had large deposits of electron-dense material; the cytoplasm was disordered, host organelles disintegrated and eventually the whole host cell disintegrated and necrotized.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.120-131
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• 1995

이 연구는 우리나라의 유용 자원식물에 발생하는 진균성 미기록 병해에 대한 두 번째 보고이다. 10가지 병해에 대한 각각의 병징, 병 발생환경, 병원균, 그리고 몇 가지 병리학적 소견을 기록하였다. 동자꽃 갈색 무늬병은 장마철부터 발생하여 심한 잎마름을 일으켰으며, 병원균은 Septoria lychnidis로 동정되었다. 산박하 모무늬병은 장마철에 심하게 발생하고 작은 모무늬가 합쳐져 잎의 한쪽이 검게 고사하였는데, 병원균은 Septoria plectranthi로 동정되었다. 좀명아주 갈색 무늬병은 여름부터 가을까지 흔히 발생하여 조기낙엽을 일으켰으며, 병원균은 Cercospora dubia로 동정되었다. 나팔꽃 점무늬병은 장마철부터 가을까지 흔히 발생하여 관상가치를 떨어뜨렸는데, 병원균은 Cercospora ipomoeae로 동정되었다. 돌콩 점무늬병은 장마철부터 가을까지 계속 발생하여 생육을 크게 저해하였는데, 병원균은 Pseudocercospora ligustri로 동정되었다. 박주가리 뒷면곰팡이병은 여름부터 가을까지 흔히 발생하여 조기낙엽과 황화를 일으켰는데, 병원균은 Passalora miurae로 동정되었다. 고려엉겅퀴 흰가루병은 여름부터 발생하여 묵나물의 수향과 품질에 피해를 주었는데, 병원균은 Sphaerotheca fusca로 동정되었다. 왜당나귀흰가루병은 국지적으로 발생하여 생육을 저해하고 어린 묘는 고사시켰는데, 병원균은 Erysiphe heraclei로 동정되었다. 가래나무 점무늬병은 장마철에서 가을까지 발생하여 잎마름을 유발하였는데, 병원균은 Sphaerulina juglandis로 동정되었다.

• Korean Journal of Microbiology
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• v.5 no.1
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• pp.24-33
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• 1967

Fifty-two specimens of the infected plants were collected from areas through the country during the year of 1965. We report here 14 unrecorded specoes which were identified in this work. The results are as follows: 1. Erysiphe cichoracearum DC. (Host: Artemisia princeps PAMPAN. var. orien-talls HARA.) 2. Erysiphe cichoracearum DC. (Host: Plantago sp.) 3. Erysiphe cichoracearum DC. (Host: Sonchus oleraceus L.) 4. Erysiphe pisi DE CANDOLLE. (Host: Lespedeza sp.) 5. Erysiphe polygoni DE CANDOLLE. (Host: Clematis patens MORR et DECAIS.) 6. Microsphaera alphitoides GRIFFITHS et MAUBLANCE (Uncinula bifurcata GERARD.) (Host: Quercus serrate GERARD) 7. Microsphaera baumleri MAGNUS. (Host: Robinia pseud-acacia L.) 8. Microsphaera coryli HOMMA. (Host: Corylus heterophylla FISCH. var. japonica KOIDZUMI) 9. Podosphaera tridactyla (WALLROTH) DE BARY. (Host: Prunus leveilleana KOEHN. var. typica NAKAI) 10. Sphaerotheca fuliginea (SCHLECHTENDAHL) POLLACI. (Host: Impatiens balsamina L.) 11. Sphaerotheca fuliginea (SCHLECHTENDAHL) POLLACI. (Host: Zinnia elegans JACQ) 12. Uncinula aceris SACCARDO (Host: Acer negundo L.) 13. Uncinula fraxini MIYABE(U. salmon SYDOW) (Host: Fraxinus rhynchophyllus HANCE.) 14. Uncinula salicis (DE CANDOLLE) WINTER. (Host: Salix gracilistyla MIQ.)

• Research in Plant Disease
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• v.8 no.3
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• pp.171-174
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• 2002

Powdery mildew of eggp1ant was found in Yeoiu, Korea in autumn 2000. Many white and Powdery mycelial colonies appeared on leaves, petioles and branches of the plants. Conidia with fibrosin bodies were ellipsoid to elongate-ellipsoid, 25~40$\times$15~22 ${\mu}{\textrm}{m}$ in size and formed in chains with crenate edge. Conidiophores were erect on superfical mycelium, 47~100 ${\mu}{\textrm}{m}$ in length. Germ tubes from conidia were simple and unbranched. No cleistoth-ecia were observed. On the basis of morphological characters of the conidial stage, the fungus was identified as Sphaerotheca fusca.

• Research in Plant Disease
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• v.16 no.3
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• pp.285-289
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• 2010

The experiments were carried out in fields for two years from 2008 to assess yield losses of squash due to powdery mildew caused by Sphaerotheca fuliginea and to determine its economic thresholds. Powdery mildew disease was first observed in late June, about 50 days after field-transplanting, progressed rapidly during late July to early August, and began to reduce from late August. Powdery mildew severity was negatively correlated with squash yields. A positive correlation was observed between fruit weight and % marketable fruits. A simple linear regression model was obtained as Y=-10.399 X + 6607.5 with $R^2$ = 0.9700 when squash yields (Y) was predicted using powdery mildew severity as an independent variable(X). Spray threshold for maximizing squash yields without economic considerations was estimated as 6.5% in terms of leaf lesion area with powdery mildew. Economic threshold and economic spray threshold able to compensate the costs of fungicide sprays were determined as 21.6% and 17.3% in leaf lesion area, respectively.

• Research in Plant Disease
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• v.10 no.1
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• pp.78-81
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• 2004

The resistance of 10 varieties of cucumber (Cucumis sativus L.) to powdery mildew, caused by Sphaerotheca fusca, was evaluated by a leaf disk assay. Leaf disks (10 mm in diameter) were removed from fully expanded leaves and then placed in petri dishes containing 0.16％ water agar amended with benzimidazole. Leaf disks were inoculated by dropping a 10 $\mu$l of conidia suspension. Conidiophore formation of powdery mildew was the greatest at $25^{\circ}C$. The response of the host to powdery mildew, based on the inoculation onto disks of the first leaf, highly correlated with results obtained from harvesting stage of cucumber plants in greenhouse test (r = 0.99$^{**}$). It is indicating that a leaf disk assay may precisely predict the response of cucumber plant to S. fusca.a.